UVES

UVES, the Ultraviolet and Visual Echelle Spectrograph, is a high-resolution optical spectrograph operated by the European Southern Observatory (ESO) on the Very Large Telescope (VLT). Installed on Unit Telescope 2 (Kueyen), UVES has been a workhorse for detailed spectroscopy since the early 2000s and remains in regular use for a wide range of astronomical programs.

Design and capabilities: UVES is a cross-dispersed echelle spectrograph offering high spectral resolution across a broad wavelength range. It has two separate arms, commonly referred to as UVB and VIS, which can observe two wavelength intervals simultaneously through a dichroic beam splitter. The instrument covers roughly 300 to 1100 nanometers, spanning from near-ultraviolet to near-infrared light, with resolving power typically in the tens of thousands to over 100,000, depending on slit width and configuration. Observations employ selectable slits and, in some setups, image slicers to optimize resolution and throughput. Wavelength calibration is provided by standard arc lamps, and data are reduced with ESO-provided software pipelines.

Applications: UVES enables precise chemical abundances and stellar atmospheric studies, high-precision radial velocities, measurements of interstellar and intergalactic absorption lines, and investigations into exoplanet atmospheres and fundamental physics. Its high resolution and broad coverage make it a foundational instrument for investigations requiring detailed spectral information and accurate wavelength calibration.

Status and impact: Built with broad European collaboration, UVES has contributed extensively to stellar, galactic, and extragalactic spectroscopy. It continues to be a key facility instrument on the VLT, supporting both legacy surveys and targeted follow-up observations.